[@max corrigan] Everyone finds Franzis’ initial registration setup annoying, so I understand your frustration. However they offer many free useful programs, and once your account is set up, future registrations are relatively easy. It’s still annoying to have to enter the serial number twice, but it can be done by copy-paste and paste. I’ve never had a problem with them as I’ve had with others (registration server down, legitimate serial numbers rejected, serial numbers having to be entered manually, impossible CAPTCHA challenges, etc.).
You need to enter your customer number and your SN to download; both are clearly shown on an email from them and can be copy-pasted from there.